SOLUTION: I have been trying to work a problem and the answer I come up with does't seem correct. The problem is as follows: In an unusual salary arrangement for a temporary worker hired

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Question 253431: I have been trying to work a problem and the answer I come up with does't seem correct. The problem is as follows:
In an unusual salary arrangement for a temporary worker hired for 30 days, the pay on the first day is 1 cent, on the second day it is 2 cents, and the pay doubles each day. What is the total pay for the 30 days worked.
My answer is - $80,530,636.95 which doesn't seem right. Wondering where I am going wrong.
Lori

Found 3 solutions by hokies, richwmiller, Theo:
Answer by hokies(65) About Me  (Show Source):
You can put this solution on YOUR website!
The answer is: pay = 2^days - 1 (in cents; test it out for yourself for the first few days)
So pay = 2^30-1 = 1073741823 cents = $10737418.23

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
This a classic for shock value.
It is usually done on chess board with 64 squares.
After 30 days it will be 2^29 since it is 2 on the second day
day 1 1
day 2 2^1
day 3 2^2
day 4 2^3
day 30 2^29
2^29=536 million, 870 thousand and 912 cents

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
30 days.
start 1 cents.
doubles each day.
total pay for 30 days?

sounds like a geometric sequence.

formulas for geometric sequences are

a%5Bn%5D+=+a%5B1%5D%2Ar%5En-1

a[n] is the nth term in the sequence.
r is the common ratio
n is the number of terms in the sequence.

s%5Bn%5D+=+a%5B1%5D%2A%281-r%5En%29%2F%281-r%29

s[n] is the sum of the terms in the sequence.

example:

let a[1] = 1
let r = 2
let n = 5

a%5Bn%5D+=+a%5B1%5D%2Ar%5En-1 becomes:

a%5B5%5D+=+1%2A2%5E4 = 16

the 5th term in the sequence is 16.

the sequence is:

1, 2, 4, 8, 16

you can see that it doubles each time.

s%5Bn%5D+=+a%5B1%5D%2A%281-r%5En%29%2F%281-r%29 becomes:

s%5Bn%5D+=+1%2A%281-2%5E5%29%2F%281-2%29 = -31%2F%28-1%29+=+31

the sum of the sequence is 31.

1 + 2 + 4 + 8 + 16 = 31.

in your problem, n = 30

s%5Bn%5D+=+1%2A%281-2%5E30%29%2F%281-2%29 = -1073741823 / -1 = 1073741823 cents.

this equals:

$10,737,418.23

try the following link to read more about geometric sequences.

http://www.wtamu.edu/academic/anns/mps/math/mathlab/col_algebra/col_alg_tut54d_geom.htm